Activation of the phagocyte respiratory burst oxidase requires interaction between the oxidase components p47(phox), p67(phox), p22(phox), and gp91(phox). IFN-γ induces transcription of the genes encoding p67(phox) (the NCF2 gene) and gp91(phox) (the CYBB gene) during monocyte differentiation, and also in mature monocytes. In these studies, we identify an NCF2 cis element, necessary for IFN-γ-induced p67(pnox) expression, and determine that this element is activated by cooperation between the transcription factors PU.1, IFN regulatory factor 1 (IRF1), and the IFN consensus-binding protein (ICSBP). Previously, we identified a CYBB cis element, necessary for IFN-γ-induced gp91(pnox) expression, and also activated by this transcription factor combination. In these investigations, we determine that recruitment of a coactivator protein, CBP (the CREBbinding protein), to the CYBB or NCF2 promoter is the molecular mechanism of transcriptional activation by PU.1, IRF1, and ICSBP. Also, we determine that the multiprotein interaction of CBP with PU.1, IRF1, and ICSBP requires either the CYBB- or NCF2-binding site. Because IFN-γ induces simultaneous expression of p67(phox) and gp91(phox), these investigations identify a molecular event that coordinates oxidase gene transcription during the inflammatory response. Also, these investigations identify CBP recruitment by cooperation between PU.1, IRF1, and ICSBP as a novel molecular mechanism for IFN-γ-induced activation of myeloid genes that are involved in the system of host defense.
|Original language||English (US)|
|Number of pages||11|
|Journal||Journal of Immunology|
|State||Published - Dec 1 1999|
ASJC Scopus subject areas
- Immunology and Allergy